Sweeper base



FIG. 1 is a front perspective view of a sweeper base which embodies our design;

FIG. 2 is a front view thereof;

FIG. 3 is a rear view thereof;

FIG. 4 is a right side view thereof,

FIG. 5 is a left side view thereof; and,

FIG. 6 is a top view thereof.

The drawings include dotted lines that form no part of our design. 

The ornamental design for a sweeper base, as shown and described. 